ThreadSendSignal (Function)

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Synchronizing the threads

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See also

ThreadSendSignal (Function)

In french: ThreadEnvoieSignal

The current thread sends an event to the specified thread in order to unlock it. This function simplifies the synchronization between threads without having to implement an advanced management of events.

Reminder:

A thread is a process run in parallel of current application (main thread). This allows you to run a task in background task for example (backup, ...).
ThreadWaitSignal and ThreadSendSignal are used to synchronize the threads two by two.

Versions 15 and later

This function is now available for Android applications.

New in version 15

This function is now available for Android applications.

Versions 17 and later

This function is now available for Windows Phone applications.

New in version 17

This function is now available for Windows Phone applications.

Versions 18 and later

This function is now available in Windows Store apps mode.

This function is now available in Android Widget mode.

New in version 18

This function is now available in Windows Store apps mode.

This function is now available in Android Widget mode.

This function is now available in Windows Store apps mode.

This function is now available in Android Widget mode.

Versions 19 and later

This function is now available for WINDEV applications in Linux.

This function is now available for WEBDEV sites in Linux.

This function is now available for iPhone/iPad applications.

New in version 19

This function is now available for WINDEV applications in Linux.

This function is now available for WEBDEV sites in Linux.

This function is now available for iPhone/iPad applications.

This function is now available for WINDEV applications in Linux.

This function is now available for WEBDEV sites in Linux.

This function is now available for iPhone/iPad applications.

Versions 21 and later

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

New in version 21

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

Example

See additional examples

// Create an event
EventCreate("Let's go", eventManual, eventClose)
// Run a first thread
ThreadExecute("Thread1", threadNormal, "Thread_First")
// Locks the current thread until the event is obtained
ThreadWaitSignal()

// Run a second thread
ThreadExecute("Thread2", threadNormal, "Thread_Second")
// Locks the current thread until the event is obtained
ThreadWaitSignal()

// Modifies the event to run the threads
EventChange("Let's go", eventOpen)

//----------------------------------------------
PROCEDURE Thread_First()
Trace(dbgInfo(dbgProcess) + " - ThreadSendSignal(threadMain)")
ThreadSendSignal(threadMain)
EventWait("Let's go")
Trace(dbgInfo(dbgProcess) + " - Event received")

//--------------------------------------------
PROCEDURE Thread_Second()
Trace(dbgInfo(dbgProcess) + " - ThreadSendSignal(threadMain)")
ThreadSendSignal(threadMain)
EventWait("Let's go")
Trace(dbgInfo(dbgProcess) + " - Event received")

Syntax

ThreadSendSignal(<Thread name>)

<Thread name>: Character string (with quotes)

Name of the thread to which the event must be sent. To send an event to the main thread, use the character string "." or the threadMain constant.
No event can be sent to the current thread.

Remarks

Synchronizing the threads

ThreadWaitSignal and ThreadSendSignal are used to synchronize the threads two by two. To synchronize several threads on the same event, the event management functions must be used:

EventCreate: Creates an event.
EventWait: Locks the current thread and waits for the event.
EventChange: Modifies the status of an event.
EventDestroy: Destroys an event.

Note: The internal mechanisms for managing the queues and stacks allow you not to synchronize the threads (Enqueue and Dequeue for the queues, Push and Pop for the stacks).

Component : wd240vm.dll